Abstract

Many-particle electron-phonon interaction effects in two-dimensional electron gases are investigated within a Born–Markov approach. We calculate the electron-phonon interaction on a microscopic level to describe relaxation processes of quantum confined electrons on ultrafast time scales. Typical examples, where two-dimensional electron gases play a role, are surfaces and two-dimensional nanostructures such as graphene and quantum wells. In graphene, we find nonequilibrium phonon generation and ultrafast cooling processes after optical excitation. Electron relaxation dynamics at the silicon (001) surface exhibits two time scales, corresponding to intrasurface and inside bulk-scattering processes. For GaAs quantum wells, we present broad emission spectra in the terahertz range assisted by LO-phonons of the barrier material.

Abstract

Many-particle electron-phonon interaction effects in two-dimensional electron gases are investigated within a Born–Markov approach. We calculate the electron-phonon interaction on a microscopic level to describe relaxation processes of quantum confined electrons on ultrafast time scales. Typical examples, where two-dimensional electron gases play a role, are surfaces and two-dimensional nanostructures such as graphene and quantum wells. In graphene, we find nonequilibrium phonon generation and ultrafast cooling processes after optical excitation. Electron relaxation dynamics at the silicon (001) surface exhibits two time scales, corresponding to intrasurface and inside bulk-scattering processes. For GaAs quantum wells, we present broad emission spectra in the terahertz range assisted by LO-phonons of the barrier material.